Yes, it actually seems to be possible to have Firefox 2 and 3 installed separated from each other on your computer and either run the older or newer version as you desire, especially useful when you are not sure whether the one or the other vital add-on will work with the new Firefox.
- When it comes to install Firefox3 it is important to select “Custom Install” and specify a different path for Firefox 3, like for example "C:\Program Files\Mozilla Firefox3".
- The installation will create an icon on your desktop to launch the new Firefox. First of all you should change it as described in the procedure mentioned above to use the right profile. In my case this is Target = “C:\Program Files\Mozilla Firefox3\firefox.exe" -P firefox3 -no-remote” ( firefox3 is the name I had chosen for the new profile ).
- Now you might want to create a second icon to launch good old Firefox 2. Rename the shortcut icon I mentioned above to e.g. “Mozilla Firefox 3”, then create a copy on your desktop and rename it to “Mozilla Firefox” or “Mozilla Firefox 2”. Change the path everywhere ( in “Target” and “Start in” ) to the directory where your old Firefox is installed, in my case: "C:\Program Files\Mozilla Firefox". Now change Target = “"C:\Program Files\Mozilla Firefox\firefox.exe" -P default -no-remote”.
- When you launch Firefox from another application, e.g. your feed reader, you might notice that through the installation of Firefox 3 your default browser has been changed to Firefox 3. In case you want to change this, launch old Firefox, go to Tools – Options – Main and click on “Check Now” besides “Always check to see whether Firefox is your default browser during startup” ( it is not necessary to enable that option ! ). Your Firefox 2 will detect that it is not the default browser anymore and will allow you to change that.
- When launching Firefox 2 through another application it may happen that it picks up the wrong profile ( if you played around with Firefox 3 before ). You realize this by the fact that all or most of your old Add-ons are gone. If this happens often you might want to decide to launch profile manager again as described in procedure above and disable option “Don’t ask at startup”. This will allow you to always manually pick the right profile when launching Firefox 2. Less convenient, but you will be on the safe side.
That’s it. Have fun with trying out Firefox 3. Many Add-ons meanwhile have been changed to support the new Firefox and pretty soon you should be able to kiss Firefox 2 good-bye !